Method and means for rotating valves



Feb. 25, 1958 A. c. SAMPIETRO 2,824,554

METHOD AND MEANS FOR ROTATING, VALVES Filed Jan. 31, 1956 5 Sheets-Sheet1 Feb. 25, 1958 A- C. SAMPIETRO METHOD AND MEANS FOR ROTATING VALVESFiled Jan. 51, 1956 5 Sheets-Sheet 2 i a Q Q \n o Y WHN v. x

Feb. 25, 1958 A. c. SAMPIETRO 2,824,554

METHOD AND MEANSYFOR ROTATING VALVES Filed Jan. 31, 1956 5 Shets-Sheet 5IZZUT Adz/Q1165 GSaZZ Dje zro Feb. 25, 1958 A. c. SAMPIETRO 2 ,5

METHOD AND MEANS FOR ROTATING VALVES Filed Jan. 31, 1956 5 Sheets-Sheet4- Adz/165 fiam ojezro Feb; 25, 1958 I ,c, s 1 0 1 2,824,554

METHOD AND NEANS FOR ROTATING VALVES 7 Filed Jan. 31,- 1956 l I. A, Z571ni 5 Sheets-Sheet 5 v 2,824,554 6 Fatented Feb. 25, 1958 METHOD ANDMEANS FOR ROTATING VALVES Achilles C. Sampietro, Detroit, Mich.Application January 31, 1956, Serial No. 562,423 23 Claims. (Cl. 123-90This invention relates generally to valve-rotating devices and moreparticularly relates to a method and means for rotating two axiallyadjacent parts by cyclically loading and unloading the parts with agenerally axially directed resultant force having a lateral componentwhich is converted into unidirectionally acting torque moments operableto rotatably drive the parts with respect to one another.

Although the principles of the present invention are of general utility,a particularly useful application is found in connection with theprovision of valve-rotating devices. It is highly desirable to providemeans for rotating engine valves since cyclic rotation of the valvesduring the course of operation thereof assists in eliminating valveburning as well as wearing, pitting and stem-galling and scoring.

In one form of valve-actuating mechanism, a spherically pivoted rockerarm is combined with a torsion spring and operates as aload-transmitting means between an engine part and a reciprocable valveassembly.

According to the principles of the present invention, a light fast valvegear of the rocker arm type is constructed to effect automatic rotationof the valve concurrently with the reciprocation thereof. Brieflydescribed, the present invention contemplates the utilize tion of arocker arm having spaced laterally-separated bearing areas engageablewith a valve on opposite sides of the valve axis. Means are provided torender the first and second bearing surfaces thus provided alternatelydominant and evasive. Accordingly, whenever force is transmitted to thevalve by the rocker arm assembly, a lateral component of force will beexhibited even though the loading and unloading forces applied to thevalve are directed in the direction of the valve axis. Accordingly, ascrubbing action occurs which is attributable to the lateral componentof force. This phenomenon is exploited in accordance with the principlesof the present invention since the lateral component of force isconverted in both loading and unloading directions into unidirectionallyapplied torque moments which rotatably drive the valve.

It is an object of the present invention, therefore, to provide a lightfast valve gear construction having a minimum moment of inertia and alighter than normal spring force and which will effect valve rotationduring the opening and closing movements of the valve.

Another object of the present invention is to provide a valve gear whichis ideally suited for conventional open clearance lash operation and isfully usable with valve gear assemblies incorporating automatic lashadjusters located anywhere in the valve gear train. I

Yet another object of the present invention is to provide a rocker armvalve assembly which will cause valve rotation both in the, opening andclosing. portion of the valve cycle. v

A further object of the present invention is to pro-' vide a rocker armactuating mechanism for a valve wherein separate keying devices are notrequired.

A still further object of the present invention is to provide a multiplevalve arrangement wherein a single spring can be employed with multiplepoppet-type valves.

Another object of the present invention is to provide means for applyinga generally axially directed force having a scrubbing component inlateral direction relative to a valve and incorporating means forconverting the lateral scrubbing component into unidirectional torquemoments for rotatably driving a valve member.

Many other features, advantages and additional objects of the presentinvention will become manifest to those versed in the art upon makingreference to the detailed description which follows and the accompanyingsheets of drawings in which preferred embodiments of the presentinvention are illustrated by way of example only. The methods of thepresent invention will best be understood from an understanding of thestructures provided herein for practicing the steps of th method.

On the drawings:

Figure 1 is a force diagram indicating schematically the theory ofoperation of the principles of the present invention;

Figure 2 is a fragmentary cross-sectional view taken generally on linell-II of Figure 3 but showing parts in elevation; a

Figure 3 is a plan elevational view of the valve gea illustrated inFigure 2;

Figure 4' is a plan elevational view of an alternative form of valvegear;

Figure .5 is a fragmentary cross-sectional view with parts .shown inelevation taken generally on line VV of Figure 4;

Figure 6 is a plan elevational view form of valve gear;

Figure 7 is a plan elevational view of an alternative form of valvegear;

Figure 8 is a cross-sectional view with parts shown in elevation takengenerally on line IXIX of Figure 7;

Figure 9 is a fragmentary cross-sectional view; and

Figure 10 is a similar fragmentary cross-sectional view illustratingalternative forms of connections provided on the end of a valve rockerarm in accordance with the principles of the present invention;

Figures 11 and 12 are generally similar views and illustrate valve gearconstructions corresponding generally to the assembly of Figures 7 and8, however, different forms of coupling connections are illustrated inaccordance with the principles of the present inven tion between theload-transmitting means and the valve stem;

Figure 13 is a fragmentary cross-sectional view with parts in elevationillustrating yet another form of coupling connection between theload-transmitting means and the valve stem in accordance with theprinciples of the present invention; a

of an alternative Figure 14 is a fragmentary plan elevational view showing yet another embodiment of the present invention";

Figure 15 is an end view of the spring of Figure Although the principlesof the present invention are of general utility, a particularly usefulapplication is made to valves for internal cenbusaen engines.Accordingly;

it is contemplated that the usual engine part is provided which isindicated generally at 20 and which will be ported to provide passagesfor fluids moving within the cavities of the engine part. The ports thusprovided are controlled by one or more valves, each valve including astem 21 carried for reciprocation and rotation by a valve stem liner 22supported by the engine part 20,

Actuating means are also provided to operate the valves in correlationwith the movement and positioning of the engine components. Accordingly,an actuating member indicated at 23 is provided and it will beunderstood that the movement of the actuating member 23 is controlled bythe usual timing gear incorporated in an internal combustion engine.

Load-transmitting means are interposed between the valve stem 21 and theengine part 20, thereby to cyclically load and unload the valve stem 21in accordance with the movements of the actuator member 23. According tothe principles of the present invention, a rocker arm indicatedgenerally at 24 is formed with a curved indentation 26 at one endthereof adapted to seat and engage against a correspondingly curvedsurface formed on the end of the actuating member 23.

The rocker arm 24 is spherically pivoted for pivotal movement relativeto an axis 26, the rocker arm 24 including an intermediate body portion27 pivotally connected to a mounting member 28 carried in firm assemblywith the engine part 20.

As shown on Figure 2, the valve stem 21 is provided with a reduceddiameter end portion 29 providing a shoulder 30 against which acollarmember 31 abuts. The collar member 31 is retained in assembly withthe valve stem 21 by means of a fastener 32 threaded onto the end of thereduced section 29 of the valve stem 21. The collar member 31 includes alower flange 33 and an upper flange 34, thereby to provide axiallyspaced shoulders each of which being inwardly crowned as at 36 and 37,respectively, to form annular bearing faces or surfaces which confrontone another.

Relating the force diagram of Figure 1 to the structure thus fardescribed in connection with Figures 2 and 3, it will be noted that theheavy line corresponds to the rocker arm 24 pivoted for rotation aroundthe pivot axis 26 and having an end portion 36 movable in a generallyvertical plane of movement to impart opening and closing thrusts to thevalve stem 21 movable on an axis of valve move ment indicated by theletters A, B.

Because the rocker arm 24 is confined for pivotal movement around theaxis 26, it will be appreciated that a true trace of the end of therocker arm 36 would lie on an arcuate path shown extended in Figure 1between the points C and D.

With the rocker arm 24 in the position with the end of the arm 36located at point E, it will be assumed that the valve gear is at theclosed valve position corresponding to the beginning of a typical valvecycle.

The rocker arm is actuated and accelerates the valve stem by theapplication of a force which is an opening force indicated by thecharacter F At the point E and with the application of the force F itwill be noted there is a small component of laterally-directed forceextending towards the right in the orientation of Figure 1, whichlateral component of force is indicated at F0 At the instant when Freaches its maximumvalue, then it should act in line with the linearmovement of the valve and no lateral component of force is exhibited.Past this point of maximum force value, however, there is a substantiallateral component of force acting towards the left, according to theorientation of Figure 1, which component is indicated in Figure 1 at F0It will be understood that the relative values of P0 and F0 aredependent upon the relationship between the axis 26 and the axiallyspaced shoulders 36 and 37 in a horizontal direction. In other words, asshown in Figure 1, greater movement below the center point iscontemplated and, accordingly, the value of F0 is indicated as beinggreater.

When the valve is fully open, the end 36 of the rocker arm 24 has moved,as indicated in Figure 1, to the point indicated at G. At this point,the accelerating force changes sign and a closing force is applied tothe valve stem 21, the closing force being indicated by F At the pointG, the closing force F indicates a horizontal component or lateralcomponent of force indicated at F0 It will be understood that if boththe force F and the force F were to be applied to the center line of thevalve stem 21, the horizontal components or lateral components of forceonly effect would be to create side thrust. If applied to the valve stem21 at some point offset from the center line axis of the valve, however,a torque moment is produced which is a function of the lateral componentof force.

Moreover, if the force F and the force F,, are applied at the same pointon the same side of the center line valve axis, the torque moment thusproduced would merely tend to oscillate the valve stem 21.

In accordance with the principles of the present invention, theapplication of the opening force and the closing force occurs onopposite sides of the center line valve axis, thereby producingunidirectionally acting torque moments which will rotatably drive thevalve stem 21 in the same direction.

It will be understood that the force diagram of Figure I greatlyexaggerates the amount of relative movement for the sake of clarity andunderstanding. In practicing the present invention, it is contemplatedthat a sulficient lateral component of force is produced to effect aso-called scrub between the components of no more than just a fewthousandths of an inch. The lateral component of force which producesthe scrubbing action, however, is exploited in accordance with theprinciples of the present invention by converting the lateral componentof motion as exhibited during loading and unloading to produceunidirectional torque moments for rotatably driving the valve. Severaldifferent embodiments of the invention exploiting the phenomena thus fardescribed are disclosed herein.

As shown in Figures 2, 3 and 9, the rocker arm 24 has a recess 26engaging the actuating member 23 on one side of the fulcrum provided bythe spherical pivot mounting member 28 and the arm portion of the rockerarm 24 on the other side of the fulcrum is adapted to operatively engagethe valve stem 21. More specifically, the rocker arm 24 is shown asincluding a bifurcated end portion providing spaced apart leg portions40 and 41 separated a distance sufficient to freely receive the reducedend section 29 of the valve stem 21. The arm portion 40 thus provides abearing area 42 lying on one side of the center line valve axisindicated at V (Figure 9) and the arm portion 41 provides a bearingsurface or area indicated at 43 lying on the opposite side of the valveaxis V, the bearing surfaces or areas 42 and 43 comprising first andsecond bearing surfaces for engaging and cooperating respectively withthe axially spaced shoulders 36 and 37 on the collar 31 firmly assembledto the valve stem 21.

In the embodiment of Figure 2, a torsion spring is provided whichfunctions as a continuous biasing means preloading the rocker arm 24 andhence the valve of which the valve stem 21 is a part towards closedposition. The torsion spring is indicated generally at 44 and has across bar 46 which extends transversely of the rocker arm 24 andunderlies and engages a portion of the rocker arm 24 on one side of thefulcrum or pivot axis 26. As shown in Figure 2, the rocker arm 24 may beprovided with an embossrnent 48 seating the cross bar 46.

At opposite ends of the cross bar 46 and on opposite sides of the rockerarm 24, a pair of coiled loops are provided. It is contemplated,according to the principles of the present invention, that the loopsherein indicated at 47 and at 48, respectively, both be wound in such adirection as to exert a biasing force against the rocker arm 24 in thesame direction, however, it is further contemplated that the spring rateof the loop 47 will vary from the spring rate of the loop 48 insufficient amount to characterize one of the loops 47, 48 as dominantand the other of the loops 47, 48 as evasive. Thus, the cross bar 46 ismade dominant on one side of the rocker arm 24 and evasive on the otherside of the rocker arm 24. This characteristic will, in turn, cause asuflicient twisting of the rocker arm 24 to etfect a similar dominantand evasive arrangement between the bearing areas or surfaces 42, 43(Figure 9) and the axially spaced shoulders 36 and 37. Thus, when therocker arm 24 is subjected to increased load greater than thepredetermined preloading eifected by the torsion spring 44 and insutlicient amount to apply a generally axially directed force to thevalve stem 21, the load will be transmitted through one of the bearingand surface areas 42 and 43 and the lateral'component of force will beconverted into a torque moment equal to the amount of the lateralcomponent of force multipled by the length of the moment, arm extendingfrom the axis V to the point of application of the force.

Because of the dominant and evasive characteristics of the valve gear,however, upon unloading the valve stem 21, the other of the bearingsurfaces or areas 42 and 43 will engage the opposite shoulders 36 and 37on the other side of the valve axis V, thereby producing a second torquemoment arm which is acting in the same direction as the torque momentarm first produced.

In other words, by making the cross bar of the spring dominant on oneside of the rocker and evasive on the other, the rocker is twisted totouch the upper flange of the collar on the valve stem on one side andthe lower flange on the other. Then as the rocker arm foreshorten's asit rotates in opening, it will cause the valve to turn one way.Likewise, it forelengthens on closing and becomes oppositely dominantand evasive due to the inertia of the valve changing direction andfavors rotation in the original direction. Thus rotation iscaused in thesame direction whether the valve is being opened or furcated ends of therocker arm 24 enveloping the flanges- 33 and 34 on the collar 31 arecaused to be twisted up and down to take up clearance at all times,thereby keeping looseness out of the valve gear to avoid noise and alsopermitting positive seating of the valve when oper-,

ated with open clearance lash. Thus, the mechanism of the presentinvention is not only ideally suited for conventional open clearancelash operation but also with automatic lash adjusters located anywherein the valve gear train. 7

The embodiment of Figures 7, 8 and 10 is generally similar to thatalready described in connection with Figures 2, 3 and 9, however, adifferent form of coupling connector is provided between the valve stemand'the load-transmitting means. of Figures 7, 8 and 10, like referencenumerals are applied to like parts wherever possible. In this form, ofthe invention, the rocker arm is indicated at 24a and is pivotallymounted to a mounting member 28a carried on the engine part 20. Anactuator recess 26a engages the In describing the embodiment actuatingmember 23. A valve stem 21a slidably mountt ed in a valve stem liner 22carried in the engine part 20 has a reduced neck indicated at 50,thereby to provide a pair of axially spaced shoulders indicated at 51and 52, respectively. Adjacent the shoulder 51 is an annular groove 53seating a retaining bead 54 formed on a dust cover 56 carried by thevalve stem 21a.

,The end of the rocker arm 24a adjacent the valve stem 21a isparticularly characterized by the formation therein of a keyhole slot 57which includes an enlarged generally circular aperture 58'and a somewhatreduced axially extending slot 59 of suflicient width to freely pass thereduced neck SQof theyalve stem 21a. There is thus.pro-. vided onopposite sides of the valve stem axis indicated at V first and secondbearing surfaces, or areas indicated by the reference numerals 60 and61, respectively, which are located on opposite ,sides of the valve axisV, for cooperativejengagementrwith corresponding axially spacedshoulders 51 and 52...,

In assembly, thet valve stern 21a passes through the enlarged hole 58whereupon the rocker arm 24a is then pulled sothereducedportion of thevalve stem, as indicated, 81 50, is trapped, in the rocker. slot neck orslot 59. Thebea'ring surfaces or areas 60 and 61.then cooperate with theshoulders 51 and-52 so that the valve stem 21a mustmove up'an'd down infollowing the movements of the rocker arm 24a.

With theernbodiment of Figures 7, 8 and 10, the continuous biasingmeans;;taking the form of' a spring, as already described in, connectionwith Figures 2 and 3,' is employed. Accordingly, like reference numeralshave been applied to the corresponding structural features of the springmeans illustrated in Figures 7 and 8. I

' lt may be noted in connection with the spring 44 that the free end ofthe loop .48 and indicated at 62 is bottomed against the engine part20.In like manner, the free end of the loop 47 as indicated at 63 islikewise bottomed against the engine part 20. The spring.44 is thusoperatively interposed between the engine part 20 and the rocker arm 24or 24ai in order tovpreload the valve towards, a closed position.

With the arrangements thus far described, it will be noted that theforce to be transmitted is onlya fraction of what is normallytransmitted through the collar fitted i to a valve stenLgAt-no timeisithe sum of the. inertia load and thevalve spring load transmitted.During the cycle, only the inertia; load of the valve itself has to behandled by the'surfa'ces in contact between the rocker.v arm and thevalve stem, or a portion of the valve s'prin'g'v force. When the valveis seated, ;.the full .force of the valve spring has to be transmittedthrough such surface and the valve stem: V

In Figure 11 amodified shown. The rocker arm is indicated *at 66Zandincludes a'generally trough-shaped element havingrupstan'ding .side 1wall portions 67. At the valve stem, the. rocker arm. 66

has enlarged bearing portions indicated at 68' and 69, respectively.Thebearin'g portions 68 and 69 together form a cylindrical innerperiphery 70 having clearance with respect to avbearing ring 71encircling a reduceddiameter" portion .72 formed on the end of a valvestem 73 supported for reciprocation and, rotation byja valveliner 74carried" in the engine part 20. A lower washer member 76 under-=- liesthe bearing ring 71 and the bearing portions 68 and 69 and an upperwashermember 77 overlies the same The washer'mernber 76and the lowermostporparts. tions of the bearing portions 68 and 69 are formedwithconfronting curved bearing "surfaces'as are the upper parts. of thebearing portions68 and 69 and-the upper washer .77. "Moreover,the'bearing-portion 68 1 and the bearing portion 69 are: relativelylongitudinally or axially ofiset to provide clearances indicatedat' 78and 79, re.

spectively. The coiled-loops 47 and 48 are arranged to be appropriatelydominant and evasive so that the'opern ing force F is directed betweenthe bearing surfaces indicated at 80 between the lower washer 76 andthebearing portion 68 and jthe closing force F is transmitted reduced end72 of the valve stem 73.

assembly by an appropriate fastener 82 connected to the form of couplingmeans is The length of the moment arm is measured from the axis of thevalve stem V to the point of application of the forces at the bearingsurfaces 80 and 81 and in Figure 11 the moment arm is indicated at 1.

In the form of the invention illustrated in Figure 12, a spool member 86is retained on a reduced diameter portion 87 formed on a valve stem 88by means of a fastener 89. The spool member 86 has a central hub portion90 and upper and lower flanges, indicated at 91 and 92, each flange 91and 92 being provided with curved or tapered bearing surfaces which areaxially or longitudinally spaced and which face one another.

[he rocker arm is indicated generally at 95 and includes upstanding sidewall portions 93. A suitable opening 94 is formed in the rocker arm 95and has clearance with respect to the hub portion 90 of the spool member86. The thickness of the rocker arm 95 is considerably less than theaxial spacing dimension between the flanges 91 and 92. Accordingly, aring member 96 is carried within the rocker arm 95 between the wallportions 93. The inner diameter of the ring member 96 provides aperipheral surface 97 having a clearance spacing relationship relativeto the hub portion 90 of the spool 86 and is of considerably lessdiameter than the outer diameter of I the flanges 91 and 92. The outerdiameter of the ring member 96, as indicated at 98, is formed tocoincide with the inside dimension of the upstanding wall portions 93 onthe rocker arm 95.

The application of an opening force to the valve results in contactbetween bearing surfaces on the lower flange 91 and the lower wallportions 99 of the rocker arm 95, as indicated by the double arrows F FUpon closing, the closing force is applied between the bearing surfacesprovided by the upper curve portion 100 of the ring member 96 and theupper flange 92, as indicated by the double arrows F F It will be notedthat the ring member 96 and the lower wall portions 99 of the rocker arm95 are suitably offset so that the torque moments will be appliedunidirectionally. In this connection, it will be noted that therespective lengths of the torque moment arms are indicated in Figure 12at L, and L In the embodiment of Figure 13, the rocker arm is indicatedat 101 and includes upstanding side walls 102 on opposite sides of abottom wall portion 103. The bottom wall is slotted, as in Figure 9, oris key-slotted, as in Figure 10, to provide an opening 104 cooperatingwith a reduced diameter portion 106 on a valve stem 107. The reduceddiameter portion 106 is bounded by a lower shoulder 108 and an axiallyor longitudinally spaced upper shoulder 109. The bottom wall 103 onopposite sides of the opening 104 is offset to provide a first bearingportion 110 and a second bearing portion 111. Thus, in opening thevalve, the forces are applied or transmitted through the engagingbearing surfaces indicated at 112 formed between the shoulder 108 andthe bearing portion 110, whereas in closing, the forces are applied ortransmitted through the bearing surfaces provided between the bearingportion 111 and the shoulder 109.

In Figures 4, and 6 and in Figures 14-17, the principles of the presentinvention are illustrated in connection with a double elementcombination. For example, an inlet valve is indicated at 120 and anoutlet valve is indicated at 121 connected to a rocker arm R, and arocker arm R in accordance with the structural arrange ment alreadydescribed. A beam member 122 is interposed between the rocker arms R andR Only a single coiled spring 123 is provided having its coils at oneend seated in a recess 124 formed in an engine part 126. The coils ofthe spring 123 at the opposite end surround a pilot portion 127 formedon a spring retainer member 128.

The upper surface of the spring retainer member 128 is particularlycharacterized by the provision of a spherically-shaped recess 129seating a spherically-shaped ball member 130 carried in firm assemblywith the beam member 122 at an opening indicated at 131.

More specifically, the beam member 122 has a central embossed bodyportion providing a substantially cylindrical or cup-shaped portion 132providing a top wall 133 and upstanding side walls 134. The side walls134 surround the spring 123. At the extremities of the side walls 133,there are provided oppositely extending arms including a first arm 134and a second arm 136. The upper surface of the arms 134 and 136 iscurved as at 137 and 138, respectively, thereby to provide a curvedbearing surface for engaging against a substantially flat bearingsurface 139 or 140 confronting one of the corresponding curved bearingsurfaces 137 and 138.

As will be evident, the tension of the spring 123 tends to keep both ofthe valves 120 and 121 closed. Each respective valve stem is trapped inthe coupling means of a corresponding rocker arm and it will beunderstood that the motion of the rocker arm is transmitted to thecorresponding valve stem in both opening and closing directions.

As the parts are never perfectly in line, each corre' sponding rockerarm R; or R will turn on its corresponding ball seat, as previouslydescribed, until its flank touches the stem of the valve, and it willtouch either on the left or the right side, according to the directionof the resultant force. That is to say, it will be touching on the leftside or on one side when the valve is opening, and on the right side oron the other side when the valve is closing.

Because each respective rocker arm R; and R is moving on a circle andthe valve stem 120 or 121 associated therewith is confined for movementalong a straight line, there is a difference or vectorial velocities andthere will be a tendency to pull the stem around. The difference ofvelocities changes sign, however, by changing the side of the valve axison which the force is applied at the same time the direction of force ischanged, unidirectional torque moments are insured so thatunidirectional rotation is effected.

Furthermore, by using the single coil spring 123 as a continuous biasingmeans for both of the inlet and outlet valve parts, it will beappreciated that the difference in opening times between the inlet andoutlet valves will result in the biasing force being rendered dominantand evasive through the beam member 122.

Figure 6 illustrates an arrangement similar to Figures 4 and 5, however,in this form of the invention, a single helically wound coil spring isindicated at 140. One end of the spring is bent back, as at 141, toapproximately the mid point of the coiled loop. The bent portion 141 isangularly offset as at 142 to provide an arm portion 143 underlying therocker arm R and engaging therewith.

The opposite end of the spring 140 is angularly offset as at 144 toprovide an arm portion 146 extending towards the center of the coiledloop. The arm portion 146 is angularly offset as at 147 to provide anarm 148 which underlies the rocker arm R Both of the arms 148 and 143are in substantially coaxial alignment and both are arranged to effect aloading of the valves 120 and 121 in a common direction.

The respective arm portions 141 and 146 are bent back preferably to themiddle of the coiled loop not only with respect to the middle, asdetermined in longitudinal direction, but also to lie on the planeintersecting the axis of the coiled spring 140. By virtue of sucharrangement, the continuous biasing force exerted upon the inlet andoutlet valves 120 and 121 is rendered dominant and evasive in accordancewith the principles of the present invention.

In the embodiment of Figures 14 and 15, the coil spring is indicated at150 and includes a wound coil disposed on an axis S which is angularlyoffset with respect to the longitudinal axis of the rocker arm R, asWell as the longitudinal axis of the rocker arm R As is more clearlyillustrated in Figure 15, one end of the coil spring 150 is brought overthe'top of the spring as at '151 to provide a laterally extending armportion. The arm portion 151 is wound sufliciently to extend downtowards the plane of the spring axis and is then bent upwardly as at 152to provide a curved bearing surface indicated at 153. 7 7

The opposite end of the spring is brought over the top as at 154 of thecoil 150 and is coiled sulficiently to extend upwardly towards the planeof thespring axis, the end of the arm 154 being curved as at 155 toprovide a bearing surface 157. It will be understood that the bearingsurfaces 153 and 157 underlie the respective rocker arms R, and RFigures 16 and 17 show the engagement between the rocker arms R and Rwith the arm portions of the respective springs illustrated inconnection with the embodiments of Figures 6 and 14. It will be notedthat the rocker arm which in Figures 16 and 17 is indicated at R, may beindented as at 170 to seat the arm portion A ofleither of the springs150 or 140. It will be understood, however, that the actual bearingsurface formed on the wire A may be crowned or curved as described inconnection with Figure 15 to effect point contact as at the point 0 inFigure 17.

'From the foregoing, it will be noted that the present inventioncontemplates the utilization of a rocker arm whereby a scrubbing forcewill be applied to the valve, the scrubbing force being themanifestation of a lateral component of force applied to the valveduring the opening and closing movements thereof. The force is renderedalternately dominant and evasive and is applied away from the axis ofthe valve to obtain unidirectional torque moments for the expresspurpose of rotating the valve unidirectionally, thereby affording all ofthe advantages ofvalve rotation without requiring an expensive separatevalve-rotating mechanism.

Although various minor modifications might be suggested by those versedin the art, it should be understood that I wish to embody within thescope of the patent warranted hereon all such modifications asreasonably and properly come within the scope of my contribution to theart.

{I claim as my invention:

1.. The method of rotating two axially adjacent partswith respect to anaxis of rotation intersecting one of the parts which includes the stepsof cyclically loading and unloading the parts with resultant axiallydirected forces having axial and lateral components, applying theloadingforce to one of the parts on one side of said axis of rotation,whereby the lateral component will produce a torque moment acting in onedirection, and applying the unloading force to said one of the parts onthe opposite side of said axis of rotation, whereby the lateralcomponent will produce a torque moment in the same one direction,whereby torotatably drive the parts with respect to one another.

. 2. The method of rotating a valve reciprocable on an axis'whichincludesthe steps of alternately and cyclically applying forces to saidvalve during the reciprocation thereof in transverse direction relativeto said axis and on opposite sides, of said axis to produceunidirectional torque moments for rotatably driving the valve.

3. The method of rotating a valve reciprocable on its axis whichincludes the steps of cyclically loading and unloading the valve withgenerally axially directed forces having a lateral component, andapplying loading force to said valve on one side of said axis and theunloadingforce on the opposite side of said axis to produce torquemoments acting in the same direction, thereby to rotatably drive thevalve during reciprocation thereof.

7 4. The method of rotating a preloaded part confined for reciprocationand rotation on a given axis of rotation, which includes the steps ofloading the part axially with a resultant minimum continuous biasingforce exhibit- 7e loading part engageable with rocker arm Queue aid? 10ing a lateral component,japplying an increasing greater than minimumload to said part-on one side of said axis of rotation to produce afirst torque moment acting in one direction, applying ayde creasin ggreater than minimum load to said part on the opposite side of said axisof rotation to produce a second torque moment acting in the sameone'direction, thereby to rotatably drive said preloaded part.

5. In combination, first and second parts, said first part beingrotatable and reciprocablerelative to said second part on a given axis,load-transmitting means between the parts engaging and loading saidfirst part on one side of said axis, and engaging and unloading saidfirst part on the opposite side of said axis, and means controlling saidload-transmitting means to load said first part with a resultant forcehaving a lateral component producing torque moments on said first partin the same direction of rotation to rotatably drive said first partwith respect to said second part.

6. In combination, first and second parts, said first part beingrotatable and reciprocable relative to said second part on a given axis,bifurcated load-transmitting means between the parts having a'loadingportion engaging said first part on one side of said axis and having anunloading portion engaging said first part on the opposite side of saidaxis, and loading means applying to said load-transmitting means aloading force having a lateral component convertible into a torquemoment acting in one direction, and applying to said load-transmittingmeans an unloading force having a lateral component convertible into atorque moment acting in the same one direction, thereby to rotatablydrive said first part during the loading and unloading thereof.

7. In combination, first and second parts being ro tatable andreciprocable on generally parallel axes, and means engaging andinterconnecting said parts and axially mechanically preloading the partsin one direction, said loading means having a first portion engaging oneof said parts under increased load and applying a lateral component offorce to said one of said parts at a point offset from one side of acorresponding one of said axes, thereby producing a torque moment actingin one direction, and having a second portion engaging said one of saidparts under decreasing load and applying a lateral component of forceoffset on an opposite side of said corresponding one of said axes,thereby producing a torque moment acting in the same one direction androtatably driving said one part.

8. The method of rotating a stemmed valve which includes the steps ofcyclically loading and unloading the valve with axially directed forceshaving a lateral scrubbing component to alternately open and close thevalve, and applying the loading and unloading forces, respectively, tosaid valve on opposite sides of its axis to produce torque momentsacting unidirectionally to rotatably drive the valve.

9. In combination, an engine part, a stemmed valve part carried forreciprocation and rotation on a given axis by said engine part, andload-transmitting means be.- tween the parts comprising a pivoted rockerarm having a fulcrum mounted on said engine part, a continuous biasingmeans between said rocker arm and said engine part preloading said valvein one direction, said continuous biasing means comprising a springmember having a cross bar extending transversely of said rocker arm andengaging said rocker arm on said one side of said fulcrum, said springmember further including a dominant coiled loop on one end of said crossbar and an evasive coiled loop on the other end of said cross bar, meanson said rocker arm on one side of said fulcrum to cyclically open andclose the valve, thereby cyclically loading and unloading the valveaxially, and means between said valve and said rocker arm on the otherside of said fulcrum comprising a collar means providing a 11 of thevalve axis during loading and providing an unloading point engaged withsaid rocker arm on the opposite side of said valve axis, therebyproducing torque moments acting unidirectionally to rotatably drive saidvalve.

10. The combination of claim 9, wherein said rocker arm is provided witha bifurcated portion having first and second generally parallel armportions engaging said collar means on opposite sides of said valveaxis.

11. The combination of claim 9 wherein said rocker arm has a slottedportion providing spaced apart first and second bearing portionsengaging said collar means on opposite sides of the valve axis.

12. In combination, an engine part, a stemmed valve part carried forreciprocation and rotation on a given axis by said engine part, andload-transmitting means between the parts comprising a pivoted rockerarm having a fulcrum mounted on said engine part, a continuous biasingmeans between said rocker arm and said engine part preloading said valvein one direction, means on said rocker arm on one side of said fulcrumto cyclically open and close the valve, thereby cyclically loading andunloading the valve axially, said rocker arm having means on the otherside of said fulcrum forming spaced bearing areas engaging said valve onopposite sides of the valve axis, said bearing areas being operativelyoffset axially to be dominant and evasive, respectively, duringunloading and loading of said valve, thereby to apply unidirectionaltorque moments for rotatably driving said valve. 7

13. In combination, an engine part, a valve part carried forreciprocation and rotation in said engine part on a given axis, saidvalve part having a cylindrical stem, means on the end of said stemproviding axially spaced first and second annular shoulders, andload-transmitting means between the parts comprising a rocker arm, meansto cyclically apply force to one end of said rocker arm, said rocker armhaving laterally spaced first and second bearing areas on the other endof said rocker arm for engaging corresponding ones of said first andsecond annular shoulders, and means between an intermediate portion ofsaid rocker arm and said engine part forming a fulcrum confining saidrocker arm for pivotal movement, whereby said rocker arm will deliverforces to said valve stem having a lateral component, and meansrendering said first and second bearing areas, respectively, dominantand evasive, thereby to utilize said lateral component of force todevelop unidirectional torque moments between said valve and said rockerarm to rotatably drive the valve part in the engine part.

14. In the combination of claim 13, said means rendering said first andsecond bearing areas respectively dominant and evasive comprising anaxial offset formed in said rocker arm between said first and secondlaterally spaced bearing areas.

15. In the combination of claim 13, said means rendering said first andsecond bearing areas respectively dominant and evasive comprising aspring member having a cross bar extending transversely of said rockerarm and engaging said rocker arm on said other end of said rocker arm,said spring member further including a dominant coiled loop on one endof said cross bar and an evasive coiled loop on the other end of saidcross bar.

16. In the combination of claim 13, said means rendering said first andsecond bearing areas respectively dominant and evasive, comprising across bar extending transversely of said rocker arm and engaging saidrocker arm at said other end of said rocker arm, said cross barcomprising one end of a coiled spring, the opposite end of said springbeing spaced transversely of said rocker arm and being confined toeffect a continuous spring-loading of said rocker arm through said crossbar.

17. In the combination of claim 13, said means rendering said first andsecond bearing areas, respectively,

- 12 dominant and evasive comprising a cross bar extending transverselyof said rocker arm and engaging said rocker arm at said other end ofsaid rocker arm, said cross bar comprising the common end of a pair ofcoiled springs on opposite sides of said rocker arm.

18. In the combination of claim 13, said means rendering said first andsecond bearing areas, respectively, dominant and evasive comprising across bar extending transversely of said rocker arm and engaging saidrocker arm at said other end of said rocker arm, said cross barcomprising a lever arm extending transversely of said rocker arm andhaving one end engaging said rocker arm at said other side of saidfulcrum, a coil spring seated on said engine part, a spring retainerbetween said lever arm and said coil spring, said lever arm and saidretainer having spherically-shaped bearing surfaces formed therebetween,and means confining the other end of said lever arm.

19. In combination, an engine part, valve means carried forreciprocation and rotation in said engine part, collar means on saidvalve means providing axially spaced first and second annular shouldersoffset from the valve axis, and load-transmitting means between saidengine part and said valve means comprising rocker arm means havinglaterally spaced first and second hearing areas at one end for engagingcorresponding ones of said first and second annular shoulders, meansbetween intermediate portions of said rocker arm means and said enginepart confining the rocker arm means for pivotal movementabout a fulcrumaxis, means at the other end of said rocker arm means for cyclicallyapplying loading and unloading forces to said rocker arm means, therebyto, in turn, deliver generally axially directed forces to said valvemeans but having a lateral component of force, and means rendering saidfirst and second areas, respectively, dominant and evasive to utilizesaid lateral component of force to develop unidirectional torque momentson the valve means to rotatably drive said valve means.

20. In the combination of claim 19, said valve means comprising a pairof spaced side-by-side valves and said means rendering said first andsecond areas, respectively, dominant and evasive, comprising springmeans preloading both of said rocker arms towards closed position.

21. In the combination of claim 20, said spring means comprising a crossbar forming a lever arm extending transversely of said rocker arm andhaving one end engaging said rocker arm at said one end of said rockerarm, a coil spring seated on said engine part, a spring retainer betweensaid lever arm and said coil spring, said lever arm and said retainerhaving spherically-shaped bearing surfaces formed therebetween, andmeans confining the other end of said lever arm.

22. In the combination of claim 20, said spring means comprising acoiled spring having an end portion forming a cross bar extendingtransversely of said rocker arm and engaging said rocker arm at said oneend of said rocker arm, the opposite end of said spring being spacedtransversely of said rocker arm and being confined to effect continuousspring-loading of said rocker arm through said cross bar.

23. In a valve actuator, a pivoted rocker arm having a lever arm portionfor engaging a valve stem and applying a generally axially directedforce exhibiting a scrubbing component in lateral direction relative tothe valve, first and second valve bearing surfaces formed thereon, andspaced on opposite sides of the valve axis, and means rendering saidfirst and second bearing surfaces alternately dominant and evasive,whereby the lateral scrubbing component will be converted intoundirectional torque moments for rotatably driving the valve.

(References on following page) References Cited in the file of thispatent UNITED STATES PATENTS Mitzelfeld et a1 Mar. 18, 1952 MansfieldJune 9, 1953 Zmuda Dec. 29, 1953 Dadd et a1. Dec. 29, 1953 Burrell Apr.17, 1956 FOREIGN PATENTS ,I\.W,W W", UNITED STATES PATENT OFFICEfiERTIFICATE OF Q0 RECTION Patent Noa 2,824,554 February 25, 1958Achilles C Sampietro It is hereby certified that error appears in theabove numbered patent requiring correction and that the said LettersPatent should read as corrected below In the grant, lines 1 to 3, forAchilles C Sampietro, of Detroit, Michigan," read Achilles 0 Sampietro,of Detroit, Michigan, assignor to Thompson Products, Inc., ofiCleveland,Ohio, a corporation of Ohio, line 12, for "Achilles C, Sampietro, hisheirs," read I'hompson Products, Inc, its successors in the heading tothe printed specification, line 3, for Achilles C, Sampietro, Detroit,Mich," read Achilles C. Sampietro,

Detroit, Mich, assignor to Thompson Products, Inc, Cleveland, Ohio, acorporation of Ohio Signed and sealed this 29th day of April 1958o(SEAL) Attest:

KARL H, AXLINE ROBERT C. WATSON Attesting Officer Commissioner ofPatents

